When the person reasonably believes that the person at whom the firearm is to be discharged possesses the means, the intent, and the opportunity of causing death or grievous bodily harm upon the person or another person.

The weapons must always be the extrema ratio, in other words: use them only when you have not any other sort of "getaway", when you have not any other chance to preserve "something" called life.
Anyway, in Italy, better never use weapons. This is valid also for law enforcements. Odd, sure it is. But the consequences are great troubles, always. Maybe for that, here, is not easy have a carry license.

i can only answer your question as to when i would use mine.i have had twice in my life when just the display of a handgun was enough.i will not go into the stories now but when i displayed handgun i did not need to point it at anyone,just the knowledge that i was carrying was enough.you must understand however that once done there is no return,i would have used it if i had to in order to defend my life or others.this message is to everyone,to take a life no matter what is something you will never forget.i have personel experiance in this and can assure you that even when your in the right it is not something you will forget.nuf said old semperfi

When the person reasonably believes that the person at whom the firearm is to be discharged possesses the means, the intent, and the opportunity of causing death or grievous bodily harm upon the person or another person.

When the person reasonably believes that the person at whom the firearm is to be discharged possesses the means, the intent, and the opportunity of causing death or grievous bodily harm upon the person or another person.

When the person reasonably believes that the person at whom the firearm is to be discharged possesses the means, the intent, and the opportunity of causing death or grievous bodily harm upon the person or another person.

Click to expand...

And two out of three isn't enough! Means, intent, and opportunity all three or you will be in the wrong.

I agree with..Agentwilblackcat_attiliomncarpenterold semperfi
And those who agree with them. Once you decide that your life is in eminent danger of severe bodily harm and /or death then your life will change forever, not just with the laywers and prosecutors who would love to blame it all on you but you will also have to live with your decision to take another life. Fortunately I have not had to make that choice yet. However, I made up my mind a long time ago that I would not ever be a victim If I could prevent it. Mess with me or my wife and you, as a criminal would have to take your chances. I will also take the consequences over defending my life or my wifes life or bashing it out in court...in case my aim was off.

Same as above and remember the rules. Know what and who you are shooting at. Shooting at a loud noise outside your window might get Junior sneaking home from his first drunken binge or the neighbors Great Dane trying to steal your garbage can lid. If you can't see them you can't shoot unless you are pretty sure the guy kicking your door in isn't the local SWAT team or an irate neighbor mad about your Fido messing up his lawn.

Some states don't require training. Haven't gotten my permit yet, but plan to. My understanding is that GA doesn't require or (that I have heard of yet) offer training of this type.
I may not be correct on this. Just going on hearsay from friends with permits.

Self defense training should not be categorized as required or not required. Its your responsibility to see that you are trained. The repercussions for being untrained can be severe and tragic.

This is really good advise. I'am sure if your involved in a shooting that the fact that you have not had any formal training will be used against you in a court of law, that is if you survive the shooting.